Some recoveries do this automatically. To be safe: manually wipe Cache and Dalvik again after flashing.
Google Apps, or GApps, are the proprietary applications developed by Google that are not included in the Android Open Source Project (AOSP) code. Because of licensing restrictions, custom ROM developers cannot bundle these apps directly into their ROMs.
Contains absolutely nothing except the Play Store, framework files, and login services. This is highly recommended for legacy devices to preserve internal storage and system RAM. Official Gapps For Android 4.1.1 Jellybean Flashable.zip
Android is free for anyone to use and change. This free version is called the Android Open Source Project, or AOSP. Custom ROM developers use AOSP to make new software for old phones.
Before you can flash any Gapps package on Android 4.1.1, you'll need the following: Some recoveries do this automatically
Boot back into recovery, perform a factory reset, and re-flash the ROM alongside a confirmed Android 4.1.1-specific GApps archive. Modern Compatibility Considerations
Think of it this way: the custom ROM gives you the "Android" experience, and the GApps package gives you the "Google" experience. Without it, you won't have access to the Play Store to download other apps, nor will you have core Google services like contact and calendar sync. Android is free for anyone to use and change
Power off the device. Press Volume Up + Power (or device-specific key combo) to enter recovery.
These are strictly for hobbyists reviving legacy hardware, such as the Asus Transformer tablets GeeksforGeeks
Update your TWRP recovery version, or open the zip on a PC, navigate to META-INF/com/google/android/updater-script , open with a text editor, and delete the lines checking for device model names.
Since OpenGApps doesn't support 4.1.1, you need to look for packages maintained by legacy enthusiasts.